Debt - Fair Value of Debt (Details) - USD ($) $ in Thousands |
Sep. 28, 2017 |
Dec. 29, 2016 |
Dec. 31, 2015 |
|---|---|---|---|
| Debt Instrument [Line Items] | |||
| Total debt at par value | $ 191,475 | $ 400,000 | $ 179,233 |
| Less: unamortized discount and debt issuance costs | 4,056 | 9,257 | 1,643 |
| Net carrying amount | 187,419 | 390,743 | 177,590 |
| Level 3 | |||
| Debt Instrument [Line Items] | |||
| Fair value | $ 191,858 | $ 400,000 | $ 179,413 |